Locating centerline

Assuming the side is a rectangle, draw diagonals (lines from alternate corners); the point of intersection will be the center of the side.

There are several ways to extend it to the length of the side--using a compass to "bisect an angle" comes to mind.

I imagine that construction is explained in more than one place on the web.

Bill

Depends on how important the exact center is-- If 'close enough' is close enough then take your ruler and find the longest axis through the oval. draw a line. Go roughly 90 degrees from that one and find the 'long spot' - draw another line. X marks the center.

If you need to be exact then- (x - a)2/p2 + (y - b)2/q2 = 1 [I have no idea what that means- it is a copy/paste from

Jim

piece of wood?

That's too easy, I like the formula better.

Balance the board on a thin straight-edge.

I guess that depends on your definition of center-line. Your method would find (the line through) the center of gravity, which may or may not be the same as the mid-point of a side.

Draw lines from each corner to the opposite diagonal corner. The intersection is the center both ways.

Joe

Draw lines from each corner to the opposite diagonal corner. The intersection is the center both ways.

Joe

piece of wood?

Where are the corners on an oblong piece of wood?

At the intersections of the edges?

On Sun, 1 Jul 2012 20:37:24 -0700 (PDT), Joe wrote in Re Re: Locating centerline:

An oblong shape does not have "corners". An oblong shape is a rectangle with the corners replaced by curves.

g piece of wood?

Huh?

Define "oblong".

That's not a definition of "oblong" I've encountered.

1. Deviating from a square, circular, or spherical form by being elongated in one direction.
2. Having the shape of or resembling a rectangle or an ellipse.
3. Botany Having a somewhat elongated form with approximately parallel sides: an oblong leaf. n. An object or figure, such as a rectangle, with an elongated shape.

I'm not Moe, but "oblong" always meant a rectangle (with four corners) when I was very young; it was only later that I saw it referred to as an elongated form of a base shape. I think some of the posters are assuming the OP meant an oval (although they make mention of a flat side, so maybe not?) and others are assuming a rectangle...